The utilisation of gaseous oxygen usually requires the use of storage tanks that must be kept under pressure, which entails relatively complicated, expensive and cumbersome equipment. These drawbacks are sometimes prohibitive. This is the case when oxygen is destined to be used as an oxidising agent in portable welding or cutting sets.
Consequently, it was proposed in European Patent Application No. EP-A-0 007 118 filed on Apr. 18, 1979 in the name of B.B.R.Instruments that oxygen be generated by catalytic decomposition of hydrogen peroxide in a particular appliance. This appliance, although very effective, has certain disadvantages. For example, the flow of oxygen and the efficiency decrease gradually over time and the performance of the appliance varies considerably depending on the origin of the hydrogen peroxide solution used. Moreover, the heat released by the decomposition of hydrogen peroxide is expelled with difficulty and the oxygen formed contains appreciable quantities of water vapour which is detrimental to the stability and the temperature of the torch flame. Finally, the design of the appliance involves maintaining a not inconsiderable dead volume of aqueous peroxide solution in the storage tank.